KR20090015110A - Method of preparing carbonaceous anode materials and using same - Google Patents

Abstract

A method for the production of carbon particles comprising selecting a precursor material, sizing said precursor material, stabilizing said precursor material, carbonizing said precursor material, and graphitizing said precursor material, wherein the precursor material has a volatile matter content of from about 5 wt.% to about 60 wt.%. A method for the production of electrode materials comprising selecting a precursor material, sizing said precursor material, stabilizing said precursor material, carbonizing said precursor material, and graphitizing said precursor material, wherein said electrode material has an average particle size of from about 1 mum to about 50 mum, a fixed carbon content of greater than about 80 wt.%, and a graphitic structure. A carbon particle having an average particle size of from about 1 mum to about 50 mum, a degree of stabilization of from about 0.1 wt.% to about 10 wt.%, a fixed carbon content of greater than about 80 wt.%, and a graphitic structure.

Description

METHODS OF PREPARING CARBONACEOUS ANODE MATERIALS AND USING SAME

Cross Reference of Related Application

Not applicable.

Statement of Federal Assistance Investigation or Discovery

Not applicable.

The present application generally relates to methods of making carbonaceous materials. More particularly, the present application relates to a method of making carbon particles for use as anode material of an electrochemical storage cell.

The requirements regarding battery performance are highly dependent on their intended use. For example, batteries for use in hybrid electric vehicles may require very long life cycles, low cost, high weight density, and high bulk density, which can add to the requirement of lightweight for batteries for portable devices such as mobile phones or camcorders. . The materials used in the construction of such batteries play an important role in the battery's ability to meet these requirements.

Carbonaceous materials, such as graphite powder, must meet several requirements in order to be used as anode materials for lithium (Li) ion batteries. The most important requirements are high coulombic efficiency in the first cycle and high reversible capacity during the charge / discharge cycle. Many methods have been developed for the production of graphite powders having the above characteristics. For example, some methods use semi-crystalline petroleum, coal tar pitch and special carbon precursor types and / or particulates such as beads or fibers. Such methods using particular carbon precursor types and / or particulates are often complex in controlling the shape and size as well as in the preparation of the desired precursor. Other methods of making such graphite powders include modifying the general surface of the carbon particles by coating the carbon particles with amorphous carbon and other materials designed to increase the coulombic efficiency in the first cycle. For example, surface modification by particle coating can include methods such as chemical vapor deposition and pitch coating. Whether using special precursors or performing surface modifications, these methods add significant cost to produce graphite powders with the desired properties.

Thus, there is a need for a low cost method of producing carbon particles suitable for use as an anode material for batteries.

Brief summary of some preferred embodiments

Herein, selecting a precursor having a volatile content of about 5% to about 60% by weight, sizing the precursor, stabilizing the precursor, carbonizing the precursor, and the bulb Disclosed is a method of making carbon particles comprising graphitizing a material.

 Also provided herein is an average particle size comprising: selecting a precursor, sizing the precursor, stabilizing the precursor, carbonizing the precursor, and graphitizing the precursor. Disclosed is a method of making an electrode material having from 1 μm to about 50 μm, with a fixed carbon content above about 80 wt% and having a graphite structure.

Also disclosed herein are carbon particles having an average particle size of about 1 μm to about 50 μm, a stabilization degree of about 0.1 wt% to about 10 wt%, a fixed carbon content of greater than about 80 wt%, and a graphite structure. .

The present invention also includes selecting a precursor having a volatile content of about 5% to about 60% by weight, sizing the precursor, stabilizing the precursor, and graphitizing the precursor. Disclosed is a method for producing carbon particles.

The paragraphs outline the features and technical advantages of the present application in order that the detailed description that follows may be better understood. Additional features and advantages of the present invention will be described below. The disclosed concepts and specific embodiments can be readily used as a basis for modifying or devising other structures for carrying out the same purposes of the present invention. Such equivalent structure may also be recognized by one skilled in the art without departing from the scope of the invention as set forth in the appended claims.

For detailed description of the preferred embodiments of the present invention, reference is made to the accompanying drawings.

1 is a process flowchart in the production of carbon particles.

2 is a graph of capacity and coulombic efficiency versus cycle number.

The present application discloses a method of making carbon particles that may be suitable for use as the anode material of a Li ion battery. The methods described herein allow for the inexpensive production of carbon particles with increased initial coulombic efficiency and reversible capacity during charge / discharge cycles. One embodiment 100 of the method shown in FIG. 1 includes at least precursor selection, sizing, stabilization, carbonization and graphitization steps. It is understood that these process steps are performed independently, and thus any combination of these steps can be considered. Alternatively, the methods can be performed in the order described herein.

According to a particular embodiment, the method 100 begins with the selection of precursor in step 10. The precursor may be a carbon-generating hydrocarbon. Alternatively, the precursor may be a carbon-generating hydrocarbon whose particles do not foam or melt when continuously heated to a temperature above about 200 ° C. at a rate of at least about 1 ° C./min. For example, the precursor may be, but is not limited to, green coke such as non-baked petroleum or coal tar coke, high molecular weight pitch, high molecular weight tar, or combinations thereof. High molecular weight pitch or high molecular weight tar herein refers to a pitch or tar having a component having a molecular weight greater than about 1000 Daltons.

As used herein, "pitch" refers to a residue derived from pyrolysis or tar distillation of organic material, which is solid at room temperature and consists mainly of a complex mixture of aromatic hydrocarbons and heterocyclic compounds. The pitch can be derived from the polymerization or condensation of the petroleum feedstock. Depending on the structure of the pitch, the pitch may be isotropic or quasicrystalline, which is suitable for use herein. As used herein, "coke" refers to coal tar coke and "petroleum coke," or the thermal decomposition end product during the condensation process of catalytic cracking. Since the coke is a hydrocarbon product remaining after heating a high boiling hydrocarbon to a temperature below 625 ° C., it may contain hydrocarbons that can be released as volatiles during subsequent heat treatment at temperatures below 1325 ° C. In certain embodiments, the precursor comprises non-fired petroleum or tar coke, sometimes referred to as "green coke."

In one embodiment, the green coke may also be characterized by a volatile content of greater than about 5 weight percent to about 60 weight percent, or greater than about 5 weight percent to about 40 weight percent. "Volatile" herein refers to the portion of the coke that is released when the coke is heated to about 950 ° C. in the absence of air and consists of a gaseous mixture and a low boiling organic compound that condenses into oil and tar upon cooling. Volatile content of green coke can be determined according to ISO 9406: 1995 (volatile material determination by gravimetric analysis) or ASTM D3175-02 (reference test method for volatiles in analytical samples of coal and coke).

Such green coke can be obtained through the process used to make any grade of coke. For example, green coke may be obtained through, but not limited to, a fuel grade, general grade, or premium grade coke manufacturing process. Such processes are well known to those skilled in the art. In one embodiment, green coke with the disclosed features is made using any feedstock known for the manufacture of fuel grade, general grade, or premium grade coke. For example, coker feeds can include atmospheric sphere tower residues, vacuum column residues, ethylene cracker residues, decant / slurry oils from fluidized bed catalytic crackers, refinery sources Gas oil, other residue streams from the refinery source, or combinations thereof, but is not limited thereto. The volatile content of green coke can be controlled through modification of the process for producing green coke. Methods of modifying the manufacturing process to produce green coke with volatile content in the disclosed ranges are known in the art and include, for example, shortening the coker drum filling or shortening the heating / immersion time. .

In one embodiment, the method 100 proceeds to block 20 sizing the precursor. The precursor can be sized via a method suitable for the material herein to produce particles having an average particle size of about 0.1 μm to about 50 μm, or about 1 μm to about 30 μm, or about 1 μm to about 15 μm. Average particle size can be determined by any standard method for determination of particle size. Such methods are known to those skilled in the art and include, but are not limited to, for example, metal mesh bodies, optical microscopes, or single-particle optical detection measurements. In a preferred embodiment, the precursor is sized via a mechanical method such as milling.

"Milling" refers herein to a method of reducing bulk solid size. Examples of suitable milling methods include, but are not limited to, impact milling, friction milling, air jet milling, ball milling, fine media milling, and knife milling. Any mechanical milling method can be used so long as it is effective to achieve the desired particle size reduction. Such milling methods, conditions and apparatus are known to those skilled in the art. The precursor milled to the disclosed average particle size may consist primarily of granulated particles. Hereinafter, precursors sized to the disclosed ranges are referred to as “sized particles”.

Referring back to FIG. 1, the method 100 may then proceed to block 30 to stabilize the sized particles. In a preferred embodiment, the sized particles are stabilized through thermochemical treatment. Such treatments, also referred to as stabilization treatments, can be carried out under any conditions using any method known to those skilled in the art and suitable for the materials herein. In one embodiment, the stabilizing treatment comprises heating the particles to a temperature of about 250 ° C. to about 350 ° C. in the presence of an oxidant. Oxidizers herein refer to chemicals that can act as electron acceptors. Oxidizing agents are well known in the art. Examples of such formulations suitable for use herein include oxides such as air, oxygen gas, organic acids, inorganic acids, metal salts and NaNO ₃ ; High valency transition metal oxides such as KMnO ₄ , K ₂ Cr ₂ O ₇ , or combinations thereof. Such agents can be used to incorporate oxygen into the sized particles, and the extent to which oxygen incorporation occurs is referred to herein as stabilization. The degree of stabilization (ie, oxygen incorporation) can be determined through any technique known to assess oxygen incorporation into particles. For example, the degree of stabilization can be determined through increasing the real weight during stabilization. In one embodiment, the substantial weight gain during stabilization is about 0.1% to about 20% by weight, preferably about 0.1% to about 10% by weight, more preferably about 0.5% to about 3% by weight.

In some embodiments, the material herein after stabilization will comprise sized particles, large particles, and hard aggregates of the above-described average size. Large particles and hard aggregates can be separated from the sized particles by conventional separation methods known in the art. For example, large particles and hard aggregates can be separated from the sized particles by sieving through a fine screen having the desired mesh size. Hereinafter, the sized particles processed through the steps indicated by block 30 in FIG. 1 are referred to as sized and stabilized particles.

In some embodiments, method 100 ends with block 40 that carbonizes and graphitizes the sized and stabilized particles. Both carbonization and graphitization are heat treatments. Carbonization primarily functions to increase the carbon: hydrogen ratio of the material, and graphitization is designed to promote the formation of graphite crystal structures.

Sized and stabilized particles may be carbonized and graphitized by any method suitable for the materials herein. In one embodiment, the sized and stabilized particles are heated by heating the particles for a time sufficient to obtain a carbon content of greater than about 80% by weight in an inert environment at a temperature of about 400 ° C to about 1500 ° C, or about 800 ° C to about 1100 ° C Carbonized. Carbonization may be performed for about 1 minute to about 4 hours. Inert environments can include, but are not limited to, nitrogen gas, argon gas, helium gas, carbon monoxide, carbon dioxide, or combinations thereof. Carbonization of the sized and stabilized particles under the disclosed conditions may yield particles having a fixed carbon content of about 80 wt% to about 98 wt%, or about 85 wt% to about 95 wt%. The carbonized sized and stabilized particles as described below are referred to as "sized and stabilized carbonized particles".

In a preferred embodiment, the sized and stabilized carbonized particles are further graphitized. Graphitization of the sized and stabilized carbonized particles may be performed for about 1 minute to 2 hours in an inert environment as described above at a temperature above about 2000 ° C., or above about 2500 ° C., or above about 3000 ° C. Sized and stabilized carbonized particles herein are sometimes referred to as “treated carbon particles”.

In some embodiments, the carbonized and graphitized materials herein will include sized and stabilized carbide graphitized particles, large particles, and hard aggregates of the above-described average size. As mentioned above, large particles and hard aggregates can be separated from sized and stabilized carbide graphitized particles.

Treated carbon particles prepared as disclosed herein can be used to form electrodes such as, for example, anode materials of electrical storage cells or rechargeable batteries. Techniques for forming the treated carbon particles herein as anodes are known to those skilled in the art. Such anodes can also be used in the construction of rechargeable batteries, including Li-ion batteries. Techniques for making such batteries are also known in the art. In one embodiment, a method of making an electrochemical storage cell comprises incorporating the treated carbon particles herein into an anode of the electrochemical storage cell.

In certain embodiments, the methods disclosed herein can produce treated carbon particles having some or all of the following characteristics: an average particle size of about 1 μm to about 50 μm, from about 0.5% to about 10% by weight Degree of stabilization, fixed carbon content above about 80% by weight and graphite structure. Particles having all of the disclosed properties can be prepared by further treating the particles that have been disclosed but lacking all of the features described above. Another method of preparing particles having these features is known to those skilled in the art and includes, without limitation, carbonization and / or graphitization.

For the invention described generally, the following examples are given as specific embodiments of the invention to demonstrate the practice and advantages of the invention. The examples are illustrative only and do not in any way limit the specification or claims.

Example 1

This example demonstrates the effect of using sodium nitrate as the oxidant in the stabilization step. Petroleum green coke was selected as a precursor. The carbon content of this petroleum coke is about 71% by weight. The carbon content was determined by heating the coke at 1000 ° C. in nitrogen gas for 2 hours. In this example, green coke was ground and milled into fine powder with an average particle size of about 9 μm (10% for less than 3 μm, 90% for less than 14 μm).

34 g of milled petroleum coke powder was mixed with a solution of sodium nitrate (LiNO ₃ ) consisting of 0.75 g LiNO ₃ , 10 g deionized water and 2 g acetone. The resulting mixture was dried at 40 ° C. under vacuum for 3 hours. The resulting powder is heated to 250 ° C. at 1 ° C./min and left at 250 ° C. for 3 hours, then heated to 300 ° C. at 1 ° C./min, left to stand for 3 hours, and finally 1000 at 3 ° C./min. Heat to C and leave at 1000 C for 2 hours. The material was then cooled to room temperature at 4 ° C / min. All heating steps were carried out under a nitrogen gas atmosphere. In this example, the stabilization step (temperature below 300 ° C.) and then the carbonization step were carried out without moving the green coke. LiNO ₃ was used as oxidant.

The carbonized powder contained several large hard masses or aggregates, which were removed by sieving through a 400-mesh screen. The remaining 400 mesh powder was graphitized for 45 min at 3000 ° C. in argon (Ar). The resulting graphite powder was then tested as anode material for lithium ion batteries as described below.

The graphite powder was evaluated as an anode material for a lithium ion battery in a coin cell having a lithium metal foil as another electrode. The powder was subjected to a thin film on a copper substrate with a composition of 7% by weight polyvinylidene fluoride (PVDF). In preparing the electrodes, graphite powder and 10 wt% PVDF solution were first thoroughly mixed in the composition to form a uniform slurry. The resulting slurry was cast to copper foil using a hand doctor blade. The cast membrane was then dried for 30 minutes on a hot plate at 110 ° C. and then pressed to a density of about 1.3 g / cc using a hydraulic rolling press.

A 1.65 cm ² disc was punched out of the film and used as the anode of the coin cell for the electrochemical test. The other electrode was lithium metal. Glass matt (Whatman FG / B *) and porous polyethylene film (Cellgaurd ™ 2300) were used as the separator between the electrode and the Li metal foil. Both the electrode and the separator were immersed in 1 M LiPF ₆ electrolyte. The solvent for the electrolyte consisted of 40 wt% ethylene carbonate, 30 wt% diethyl carbonate, and 30 wt% dimethyl carbonate. First charge the cell under a constant current of 1 mA until the cell voltage reaches 0.0 volt, charge for a further hour at a constant voltage of 0.0 volt, or charge until the current drops below 50 μA, and then Under discharge until the cell voltage reached 2.0 volts. The Coulomb number passed during charge and discharge was recorded and used to determine the capacity and coulombic efficiency of the graphite particles in each cycle. All tests were performed at room temperature (about 23 ° C.). Table 1 shows the discharge capacity and the coulombic efficiency in the first and fifth cycles.

Example 2

This example is similar to Example 1 but uses relatively excess sodium nitrate as compared to Example 1 as the oxidant. First, the same 22.0 g of petroleum coke powder as in Example 1 was mixed with a solution of sodium nitrate (NaNO ₃ ) consisting of 1.7 g NaNO ₃ , 5 g deionized water and 2 g acetone. The resulting mixture was dried and subjected to heat treatment for stabilization and carbonization in the same manner as in Example 1.

The carbonized powder contained a large amount of aggregates less than in Example 1. Again, before graphitization, large aggregates were removed by sieving with a 400-mesh screen. 400 mesh powder was graphitized under the same conditions as in Example 1, and the resulting graphite powder was tested in the same manner as in Example 1. The test results are shown in Table 1. Furthermore, the recharge capacity of the graphite powder was tested over five cycles. Capacity and coulombic efficiency are plotted in FIG. 2.

Example 3

This example is similar to Example 2 in terms of oxidant and amount, but with an average particle size. The same petroleum green coke as in Example 1 was used in this example. First, petroleum coke was jet-milled to an average particle size of about 15 μm (less than 7 μm 10% and 30 μm 90%), and 23.O g of milled petroleum coke powder was 1.8 g of NaNO ₃ , 4 g of It was mixed with a sodium nitrate solution consisting of ionized water and 2 g of acetone. The resulting mixture was dried and heat treated in the same manner as in Example 1.

Similarly, the resulting powder was sieved with a 400-mesh screen to remove large aggregates. 400 mesh powder was graphitized at 3000 ° C. in Ar for 45 minutes. The resulting graphite powder was tested in the same manner as in Example 1. The test results are shown in the table for comparison.

Example 4

This example used air as the oxidant in the stabilization step. The same 100 g milled petroleum coke powder as in Example 3 was applied to an 8 "diameter glass dish, heated to 250 ° C at 1 ° C / min and left for 3 hours, then to 290 ° C at 1 ° C / min It was allowed to stand at 290 ° C. for 10 hours under reduced pressure (about −18 ″ Hg). Green coke powder was oxidized through heating during reduced pressure, resulting in green coke particles being insoluble and not melting during subsequent carbonization and graphitization steps.

The resulting stabilized coke powder was then heated to 800 ° C. at 5 ° C./min, left at 800 ° C. for 2 hours and then cooled to room temperature in a nitrogen gas atmosphere. The carbonized powder was then graphitized at 3000 ° C. for 45 minutes under an argon gas environment. The resulting graphite powder was then tested in the same manner as in Example 1, and the test results are shown in Table 1.

Example 5

The same 100 g of milled petroleum coke as Example 1 was applied to an 8 "diameter glass dish similar to Example 4 and heat treated in the same manner as Example 4 in all steps (stabilization, carbonization, and graphite). Graphite powder Table 1 shows the test results.

Comparative Example

Comparative Example 1

In this example, the green coke powder may be coated with petroleum pitch and then heat treated to obtain a product having electrochemical properties similar to that of Example 1, but the path is somewhat complicated.

The same 21 g of petroleum coke powder as Example 3 was dispersed in 100 g of xylene to form Solution A in a sealed stainless steel container and heated to 140 ° C. during which the solution was continuously shaken. At the same time, 40 g of petroleum pitch was dissolved in 40 g of xylene to form solution B. Solution B was also heated to 140 ° C. and then poured into Solution A and mixed thoroughly. The resulting solution was heated at 180 ° C. for 10 minutes and then cooled to room temperature, during which time the solution was shaken continuously. The resulting solid powder was separated via filtration and washed twice with 50 ml of xylene and then dried under vacuum. The resulting dry powder was 23.8 g and had a 16% pitch in the powder.

The powder is applied to a glass dish (approximately 4 inch diameter), placed in a furnace and heated to 160 ° C. at 5 ° C./min and 250 ° C. at 1 ° C./min under reduced pressure (about −15 inch Hg). After standing at 250 ° C. for 2 hours, it was heated to 280 ° C. at 1 ° C./min and left at 280 ° C. for 8 hours, and then cooled to room temperature. Oxygen gas in air was reacted with the coated pitch during heating. As a result, the pitch film reacted on the carbon particles became insoluble and could obtain the desired crystal structure during the subsequent carbonization and graphitization steps.

The powder was placed in a tube furnace and heated at 800 ° C. for 2 hours in nitrogen gas and then cooled to room temperature (about 22 ° C.). The resulting powder was then transferred to an induction furnace, heated for 45 minutes at 3000 ° C. in argon gas and then cooled to room temperature. The resulting graphite powder was tested in the same manner as in Example 1, and the test results are shown in Table 1 for comparison.

Comparative Example 2

This example shows the effect of different petroleum coke. The green petroleum coke used in this example contained about 92% carbon content as compared to 71% of Example 1. When this petroleum coke powder was heated rapidly in nitrogen gas, it did not sinter or foam. In this example, 100 g of milled petroleum coke powder (average particle size about 8 μm) is applied to an 8 ”diameter glass dish, heated to 250 ° C. at 1 ° C./min and left for 3 hours, and 1 ° C./min Heated to 290 ° C. and left under reduced pressure (about −18 ″ Hg) at 290 ° C. for 10 hours.

The resulting coke powder was then heated to 800 ° C. at 5 ° C./min and left at 800 ° C. for 2 hours, then cooled to room temperature in a nitrogen gas atmosphere. The carbonized powder was then graphitized at 3000 ° C. for 45 minutes under argon gas environment. The resulting graphite powder was tested in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 3

This example demonstrates the benefits of the stabilization step of petroleum green coke in Example 1. The same 100 g of petroleum coke as Example 1 was heated to 800 ° C. at 5 ° C./min and left at 800 ° C. for 2 hours in nitrogen, then cooled to room temperature. The resulting powders were sintered together. Such hard sintered materials cannot be used unless they are ground again. Thus the material could not be tested as a powder.

The test results in Table 1 clearly show that graphite powders prepared according to the principles disclosed herein exhibit excellent first cycle coulombic efficiency and reversible capacity.

While the preferred embodiments of the invention have been shown and described, modifications thereof can be made by those skilled in the art without departing from the spirit of the invention. The embodiments described herein are illustrative only and not intended to be limiting. Many variations and modifications of the invention disclosed herein are possible within the spirit of the invention. For example, while numerical ranges or limitations are explicitly mentioned, such expression ranges or limitations should be understood to include similar degrees of gradual ranges or limitations that fall within the explicitly stated ranges or limitations (eg, about 1 to about 10 includes 2, 3, 4, etc .; greater than 0.10 includes 0.11, 0.12, 0.13, etc.). Use of the term “optionally” in connection with any component of the claims is intended to mean that such component is required or not required; Both are intended to fall within the scope of the claims. The use of generic terms, such as include, include, having, etc., should be understood to provide support for limited terminology, such as made, consisting essentially, substantially including, and the like.

Accordingly, the scope of protection is not limited to the techniques described above, but only by the following claims, which range includes all equivalents of the claims. Each and every claim is incorporated into the specification as an embodiment of the invention. Accordingly, the claims are yet another description and are added as preferred embodiments of the invention. References herein, in particular any discussion of which references may be after the priority date of the present application, are not admitted to be prior art to the present invention. The disclosures of all patents, patent applications, and publications cited herein are hereby incorporated by reference in their scope to provide examples, procedures, or other detailed supplements to those described herein.

Claims (25)

(a) selecting a precursor having a volatile content of about 5% to about 60% by weight; (b) sizing the precursor; (c) stabilizing the precursor; (d) carbonizing the precursor; And (e) graphitizing the precursor Method for producing a carbon particle comprising a. The method of claim 1 wherein the volatile content of the precursor is from about 5% to about 40% by weight. The method of claim 1 wherein the precursor is a carbon-yielding hydrocarbon. The method of claim 1 wherein the precursor is non-fired petroleum coke, non-fired coal tar coke, high molecular weight pitch, high molecular weight tar, or a combination thereof. The method of claim 1 wherein the precursor is a green coke. The coke feedstock according to claim 5, wherein the coke feedstock is an atmospheric sphere residue, a vacuum distillation tower residue, an ethylene cracker residue, a decant or slurry oil from a fluidized bed catalytic cracker, or a combination thereof. Way. The method of claim 1, wherein the precursor is sized to an average particle size of about 1 μm to about 50 μm. The method of claim 1, wherein the precursor is sized to an average particle size of about 1 μm to about 30 μm. The method of claim 1, wherein the precursor is sized to an average particle size of about 1 μm to about 15 μm. The method of claim 1, wherein the sizing of the precursor is by mechanical milling. The method of claim 1, wherein the stabilizing treatment comprises heating the precursor in the presence of an oxidant. The method of claim 11, wherein the precursor is heated to a temperature of about 250 ° C to about 350 ° C. The method of claim 11, wherein the oxidant is air, oxygen gas, organic acid, inorganic acid, metal salt, metal oxide, high valence transition metal oxide, or a combination thereof. The method of claim 1 wherein the degree of stabilization of the precursor is from about 0.1% to about 20% by weight. The method of claim 14, wherein the degree of stabilization is measured as an increase in the real weight of the precursor during stabilization. The method of claim 1, further comprising separating large particles and hard aggregates from the precursors after stabilization. The method of claim 1, wherein step (b) is performed between step (a) and step (c). The method of claim 1, wherein the precursor is carbonized in an inert environment at a temperature of about 400 ° C. to about 1500 ° C. 5. The process of claim 1 wherein carbonization produces a precursor having a fixed carbon content of greater than about 80 weight percent. The method of claim 1, wherein the precursor is graphitized at a temperature above about 2000 ° C. 3. The method of claim 1 wherein steps (d) and (e) are performed after step (c). The method of claim 1, further comprising separating large particles and hard aggregates from the precursor after step (e). (a) selecting a precursor; (b) sizing the precursor; (c) stabilizing the precursor; (d) carbonizing the precursor; And (e) graphitizing the precursor Wherein the average particle size is from about 1 μm to about 50 μm, the fixed carbon content is greater than about 80 wt%, and has a graphite structure. A carbon particle having an average particle size of about 1 μm to about 50 μm, a stabilization degree of about 0.1 wt% to about 10 wt%, a fixed carbon content of greater than about 80 wt%, and having a graphite structure. (a) selecting a precursor having a volatile content of about 5% to about 60% by weight; (b) sizing the precursor; (c) stabilizing the precursor; And (d) graphitizing the precursor Method for producing a carbon particle comprising a.

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